chemistry of the atmosphere

• what is earths early atmosphere similar to?

  mars and Venus today
• what was earths early atmosphere like 4.6 billion years ago?

  • intense volcanic activity released gases
  • nitrogen
  • mainly carbon dioxide
  • virtually no oxygen
• why is earth early atmosphere hard to prove?

  no proof from 4.6 billion years ago
• what is absorbed by photosynthesis?

  carbon dioxide
• what is condensed to form oceans?

  water vapour
• what do shells and skeletons form from oceans?

  carbonates
• what are layers of sediment formed from?

  carbonate precipitate
• what are 2 examples of sedimentary rocks?

  • limestone
  • coal
• when was algae evolved?

  2.7 billion years ago
• what is the symbol equation for photosynthesis?

  6CO2 + 6H2O -> C6H12O6 + 6O2
• why is the increase in atmospheric oxygen significant?

  led to evolution of animals
• what are 3 greenhouse gases?

  • carbon dioxide
  • methane
  • water vapour
• what is the greenhouse effect?

  when greenhouse gases in atmosphere absorb long wavelength radiation and reradiate it in all directions, including back towards earth, keeping earth warm
• what are the 4 causes of increased carbon dioxide and methane?

  • deforestation - less carbon dioxide is removed by photosynthesis
  • burning fossil fuels - releases carbon dioxide
  • farm animals - produce methane
  • decomposition of landfill/agricultural waste - releases carbon dioxide and methane
• what is the evidence for climate change?

  most scientists think that increased carbon dioxide levels have caused the average temperature of earths surface to increase and this will lead to climate change
• what are 4 consequences of climate changes?

  1. flooding / erosion in coastal areas due to melting of polar ice caps causing sea levels to rise
  2. more frequent / severe storms
  3. difficulty producing food in certain areas if temperatures / rainfall patterns change
  4. changes in distribution of some wild species if habitats change
• what is carbon footprint?

  how much carbon dioxide and other greenhouse gases are released over somethings full life cycle
• how can you reduce your carbon footprint?

  • by reducing carbon dioxide and methane produced
  • governments acting
• what do fossil fuels contain?

  Hydrocarbons and sulfur impurities
• what do combustion of fossil fuels products cause?

  gases and particles which produce air
• whats the formulation and effects of carbon monoxide?

  • formulation = incomplete combustion of fossil fuels
  • effects = stops blood from transporting enough oxygen around body - causes fainting, coma, death
• whats the formulation and effects of carbon particulates (soot)?

  • formulation = incomplete combustion of fossil fuels
  • effects = respiratory problems and global dimming
• whats the formulation and effects of sulfur dioxide?

  • formulation = oxidation of sulfur impurities in fossil fuels during combustion
  • effects = acid rain and respiratory problems
• whats the formulation and effects of oxides of nitrogen?

  • formulation = reaction between nitrogen and oxygen in air caused by heat of burning fuels
  • effects = acid rain and respiratory problems